High-pressure fluid pump gasketing



se t.- 3, 1946. w; T, A B 2,406,927

HIGH PRESSURE FLUID PUMP GASKETING Filed March 6, 1945 INVENT OR.

AJATToRNEv/s Patented Sept. 3, 1946 2,406,927 HIGH-PRESSURE FLUID PUMP GASKETING Warner T. Tabb, Plainfield, N. J., assignor t Eisemann Corporation, Brooklyn, N. Y., a corporation of Delaware Application March 6, 1945, Serial No. 581,289

11 Claims.

This invention relates to a high pressure fluid pump more particularly adapted for use in fuel injection systems for internal combustion engines such as those of the Diesel type, and to features of improvement disclosed in my application Serial No. 429,464, filed February 4, 1942, now Patent No, 2,372,694 granted April 3, 1945, and of which this application is a division.

A general object of the invention is the provision of such apparatus which can readily and economically be manufactured in quantity production with interchangeable parts, easily assembled and effectively and efliciently used.

A more specific object of the invention is the provision of such pump structure so constructed and arranged as to necessitate quite accurate fitting between mating parts of plunger structure and associated casing means structure, such as bushing structure, of only one relative short portion of the length thereof, e. g. of only the port section of a. plunger in a plunger bore, and with suitable provision of a low pressure fluid leakage chamber to avoid high pressure leakage.

Another object of the invention is the provision of efficient low and high pressure gasketing of a plunger bushing in a casing bore whereby effective and simple low pressure fluid sealing does not interfere with proper positioning of the bushing and whereby a plug of a discharge conduit system may directly engage the bushing and/or engage a gasket on the bushing to move and hold the bushing in a predetermined position in the pump bore and to accurately locate the plug in a predetermined position in the pump bore.

Other objects of the invention will in part be obvious and will in part appear hereinafter.

For a fuller understanding of the nature and objects of the invention reference should be had to the following detailed description takenin con nection with the accompanying drawing, in which:

Figure l is an elevational sectional view with parts broken away of casing means, a pump plunger and associated structure of one embodiment of the present invention;

Figure 2 is an elevational view of a pump plunger of the present invention;-

Figure 3 is a sectional view taken on line 3-3 of Figure 2.

The present invention is adapted for incorporation in a pump of the general type disclosed in Purdy United States: Patent No. 2,166,876 of July 18, 1939, Which as more specifically explained therein constitutes an apparatus adapted for connection to a substantially low pressure supply system such as a supply tank of fuel oil and supply and venting conduit means. In apparatus of that type there may be provided a casing structure having a substantially axially arranged bore therein in which is mounted suitable metering valve structure through which low pressure fuel may communicate through passages to a plurality of pump plunger bores, one for each cylinder of the engine, arranged circumferentially of the axial bore with, if desired, such pump plunger bores being provided by suitable plunger bush ings mounted in circumferentially arranged holes in a casing, the casing and bushings comprising casing means. These pump plunger bores may further be suitably vented to low pressure fuel supply or a chamber connected thereto cooperating in the obtainment of substantially instantaneous cut-off of fuel under high pressure supplied from suitable nozzle structure to each of the engine cylinders. Each pump plunger bore has associated therewith a suitable pump plunger for reciprocative action therein and plunger operative means such as a suitable cam device common to the plurality of pump plungers for successive operation thereof which latter structure may be located in a chamber in the cas ing structure with the chamber serving as a pump sump, and more particularly with the means for sealing and accurately locating the bushing in which the pump plunger bore is formed within the casing.

Referring to the drawing, like numerals refer tolike parts throughout. A casin I0 formed if desired of metal may, in accordance with one embodiment of the present invention, be provided with a bore ll counterbored to provide a shoulder l2 preferably tapered, that is, conforming to the surface of a truncated cone asshown, and further counterbored to provide an additional shoulder [3 which may have the surface thereof lying in a plane substantially normal to the axis of the bore. Inward of the high pressure end the bore H- is preferably internally threaded as shown at M and the outward end thereof is counterbored at l5 to receive plunger spring rigging, cam follower and associated structure. A relatively low pressure fluid passage I6 is formed therein communicating with the bore II and adapted to be connected through suitable passages and metering valve structure to a relatively low pressure fluid supply and may serve both for supplying and venting relatively low pressure fluid to and from pump plunger bore. An additional venting passage I! may also, if desired, be provided.

Bushing means are fitted into the bore H and may comprise a main bushing section I8 having the high pressure end thereof fitted into the bore II, snugly if desired, inwardly of the shoulder I3 such as at I9 for proper location of the bushing in the casing and set back in a midsection thereof such as at 20 to provide a shoulder 2| to cooperate with the bore shoulder I3 with the interpositioning therebetween of a high pressure gasket 22, formed of any suitable material such as, by way of example, dead soft copper. The bushing I8 is further set back to provide a shoulder 23 adapted to cooperate with the bore shoulder I2 and between the latter two shoulders is confined a low pressure gasket 24 formed of any suitable material such as, by way of example, Babbitt metal. In the preferred form the gasket 24 is made substantially rectangular in section and deformed (to the shape shown) by the tapered seat I2 when the main bushing section- I8 is forced into position with the high pressure gasket 22 predetermining such position. Obviously the tapered shoulder may be provided on the bushing and the right-angled shoulder in the bore II or both shoulders may be tapered if desired. Further, the gasket 24 may be provided with a tapered face to cooperate with the tapered shoulder but adapted to be further deformed when the bushing is seated in the casing bore thereby to obtain substantially low pressure fluid-tight sealing.

The gasket 22 and 24 may, if desired, be formed of similar material that may be relatively resistant to deformation but capable thereof, or relatively softer material readily capable of deformation, so long as the seating area of gasket 22 is substantially greater than that of gasket 24. The latter feature assures that gasket 24 while providing a substantially low pressure fluid-tight seal will not prevent a proper seating and sub- 'stantially high pressure fluid-tight sealing at gasket 22 when the bushing I8 is forced into the casing bore II to a desired position determined by the cooperating shoulders I3 and 2| and gas ket 22. The arrangement would be such that the low pressure gasket 24 would be adapted to be considerably deformed, relatively speaking, by positioning of the bushing in casing, whereas the high pressure gasket 22 which serves to determine the longitudinal position of the bushing in the casing is not appreciably deformed by the locating operation. Further, a substantially high pressure fluid-tight seal may be attained at shoulders I3 and 2| with the omission of gasket 22 by providing a lapped joint between complementary shoulders thereat which would serve to attain the desired seal and determine the position of the bushing in the casing with the gasket 24 being deformed to attain the low pressure seal.

The gasket 24 may be made of material softer than that from which the high pressure gasket 22 is formed, such as relatively soft deformable material, for example, soft metal of little elasticity, e. g. copper, lead, alloys thereof, etc., or from resilient material such as rubber, synthetic rubber, neoprene and the like. In such case it would not be essential to make the shoulder I2 tapered or of other shape initially to provide a relatively small seating area since obviously a greater seating area, such as provided by a relatively wider, ubstantially fiat transversely extending shoulder, could be used with the attainment of similar ends.

In any case the arrangement is such that cooperating shoulders such as at I3 and 2I provide a substantially high pressure fluid-tight seal and determine the position of the bushing in the casing and a gasket such as that at 24 is deformed by shoulder such as at I2 and 23 to provide a substantially low pressure fluid-tight seal without objectionably interfering with the desired locating or positioning of the bushing in the casing. By virtue of such structure it is not necessary to have the bushing carefully fitted into the bore II throughout the length thereof and as shown it may be spaced from the bore wall between paired shoulders I3, 2! and I2, 23 and also outwardly of the latter thereby simplifying manufacturing. As a result the bushing is sealed into the casing at two different places simultaneously by the single act of sliding or forcing the bushing into the casing to a predetermined position (where it is to be held), and such locating is determined by only one pair of cooperating shoulders making for convenience in dimensioning and manufacturing to tolerances. Additionally, necessity of carefully aligning the surface of shoulder 23 with any cooperating casing surface (as would be required if a considerable area of flat gasket surface seating on opposed shoulders was used in lieu of the deformation feature characterizing the present invention) is eliminated.

Further high pressure sealing may be attained by recessing the high pressure end of the bushing I8 such as at 25 and this recess may be so formed as to provide a shoulder 26 substantially normal to the axis of the bushing and a tapered shoulder 21 substantially conforming to the surface of a truncated cone. A gasket 28 of suitable deformable material such as, by way of example, dead soft copper, which may be initially substantially rectangular in section is compressed within the recess 25 with its outside surface 29 engaging the wall of the bore I I, one fiat surface engaging the shoulder 26 and a portion deformed to conform to the tapered seat 21. This deformation is attained by the positioning of a plug 30 in the high pressure end of the bore II such as by threaded engagement therein with the end of the plug engaging the other flat face of the gasket 28. The plug 30 thus retains bushing l 8 in position in the bore II and is provided with a central opening which may have a portion thereof shaped to provide a seat for a check valve 3| which communicates with a bore in the plug adapted to receive a coupling member connecting thereto suitable conduit means leading to suitable nozzle structure in the wall of an engine cylinder (not shown) The extent to which the gasket 28 may be compressed is limited and accordingly it may be used with the associated structure accurately to limit the insertion of the plug 30 into the bore II due to the fact that after the gasket is deformed to the shape shown, flat surfaces of considerable area are engaged by shoulder 26 and the end of the plug 30. Obviously the gasket 28 may be initially formed with a bevelled surface to cooperate with the tapered surface 2'! of the bushing I8 but provided sufficiently oversized so as to obtain deformation as the plug 30 is forced into the bore I I.

aroma? Lfinal position. 'Qbviousl ,lthe material forjgasket .218 will :be :selected which will provide for the desired deformation, sealing and limiting of movement :of the .plug 30 into the end of the casing bore which, of course, will in part *be .dependent upon dimensions of associated structure relating to this feature. Fundamentally this featureis characterized by deformationo-f thegasket duringan initial portion .of the operation of .forc- ;ing the plug 30 ;into .bore ll while enablin plug -30 finally to ifind a positive seating surface :of suliicient area so that termination of its movementinto the bore is well defined and accords with a predetermined position. The final seating surface of area greater .than the initialseat- 5 :ing surface may .here :be :provided by the rel- .:ativelyilarge area offinal seating of the surfaces of the gasket 28 and the shoulder 26 and this in cooperation with resistance by the gasket material to deformation beyond a certain 'degree may determine the final 'position ofthe plug in thecasing. Alternatively the final seating of the .plug 30 may be provided by seating it on the end of the bushing :as shown in Figure '1 and referred to vmore fully hereinafter. As a con- 1 sequence this third gasketing avoids the necessity of carefully aligning cooperating surfaces of the bushing and plug and similarly carefully aligning-cooperating surfaces of the bushing and easing. A slight misalignment of the plug surface with a transverse bushing surface such as 26 and likewise similar misalignment of the end surface of the plug with the end surface of the bushing would not giverise to any problems and, of course, there is no problem of leakage here involved.

The tapered seating surfaces I2 and 21 have been chosen as a matter of convenience whereby the initial small seating area permitting increase thereof during gasket deformation is readily obtained. Obviously, however, this may be obtained by other arrangements such as stepping the shoulder whereby the seating surface for the initial seating is in one or more transverse planes but of sufficiently smalltotal area to permit'ready deformation of the gasket thereafter and provide for increase of the seating surface such as by bringing into operation additional seating surfaces in transverse planes upon such further deformation.

It will be seen that with respect to the gasketing arrangement proposed above there is provided a structure wherein a bushing is sealed to a casing against low pressure at one place without locatively determining the posit'ionof 'the bushing with respect to the casing, is sealed against high pressure at another place and its position with respect to the-casing locatively determined thereat, and, is sealed against high pressure, but not located with respect to the casing at a third place, and in addition -a plug holding the bushing assembled in the casing is first sealed and finally locatively positioned at that third place.

The bushing i8 is provided with a plunger bore 32 which, if desired, may have the high pressure end thereof counterbored as at 33 with a passage 34 communicating between the counterbored portion 33 and the passage l1. Such a feature is disclosed in the Tabb :et a1, United States Patent 2,247,421 of July 1, 1941, wherein it is explained that fluid under pressure in front of the pump plunger is vented through such passages to reduce the pressure of the fluid in the conduit to the engine cylinder sufficier-itly to permit .sa spring ibiaiSBd :valve ;in nozzle structure to ;close thereby cutting off iiuiddischarge from-the (nozzle. :Such a ifeature, howeven is not essential to ithe istructune iof the present :invention.

In the icounterbored portion of the bore .of the casing 110tis reciprocativelymounted a skirted iDr tubular plunger follower 35 having a follower roller :38 mounted therein, engaging a suitable cam surface 40 which may be .iocated in a pump sumporrcamchamber.

A pump plunger 42 of :any suitable design may be suitably fitted in :the plunger bore .32 of the bushing 1118 and preferably comprisesahigh pressure :end 43, a portse'ction :44, a sealing section 45, and an outward aoperable end 46"f0r engagement with the projecting portion 14! of the :follower 3-5 for inward :movement lthereby.

Circumambient :of the plunger 42 is arranged an :auxiliary bushing section 41 which may be .a :collar radially spaced therefrom and having a flange 48 in substantially :low pressure fluid-tight sliding engagement with the sealing section '45 of the plunger 42 to provide a leakage recess 419. 'Themaintbush'ing section l8 isprovicle'd with a -shoulder :50 which 'is engaged by one endof the collar "4;? preferably with :a transverse sliding lit to assure the formation of a leakage chamber constituted by recess 49 and freely permitting self-alignment 'of the plunger with respect to the bushing and with respect to the collar. The sorormed leakage chamber may be vented in any suitable manner such as by a passage 51 communicating with a passage 52 in communication with passage I 6. The bushing l8 maybe ported 'at'5'3.

The collar 41 may be held in engagement with the main bushing section 18 by any suitable means. By way of example, a plate 86 having a spring seating flange 81 may be mounted on the end 4 6 of the plunger 42 by placement of suitable means such as a split ring 88 in the groove 64, The opposite end of the spring 54 may 'be seated directly against casing structure as by seating it against a shoulder 89 on the casing 10 and the collar 41 maybeheld in engagement with the casing means or bushing 18 by an auxiliary spring 90 seated at one end on plate 86 and at the other end against the collar-41 or the flange 48 thereof.

Means are preferably provided on the plunger to cooperate with the flange 48 of the collar 41 so that a *subassem'bly may be provided. Such means may constitute a pin 63 located in therecess or chamber 49 and 'loosely'held in a transverse hole 69 in the plunger 42 by the collar 41.

The plunger 42 preferably is provided with a plurality of sets of supply and'venting ports selectively to be used for delivery of different quantities of fluid. The set of supply ports may be three in number arranged circumferentially of the plunger about apart as indicated in Figures 2 and '3 and may comprise ports 10, H and I2 each having a working or effective controlling edge 13 located at a certain point along the plunger. A set of venting ports are paired with thesupply'ports and may comprise the three similarl arranged as indicated at "l4, l5 and 16, each of. which has an. effective or working edge "H also arrangedat a certain point. The distance between. the edges 7-3 and T! of any pair of ports angularly positioned for cooperation with effective or Working edges of the port or ports of a passage or passages leading intothe plunger bore determines the capacity of the pump cylinder for that particular plunger position, This distance 7 minus a corresponding distance between the effective or working edges of the casing means port or ports is the length of the effective stroke of the plunger. If desired, the effective working edges of a certain pair of supply and venting plunger ports may be located at a distance apart difiering from that for other pairs of ports, which as shown only by way of example differs for any one pair of ports. With one port provided by passage 53 in the bushing serving both as a bushing supply port and bushing venting port for each plunger bore, as shown by way of example in the structures depicted in the drawing, this distance between effective edges of bushing ports is the distance between a leading effective edge 53l and a trailing effective edge 532 which is the same for all pump cylinders and for all positions of any one pump plunger, The effective stroke of any one pump plunger of the depicted structures for any one pair of supply and venting ports is the distance between edges 13 and 1'! thereof minus the distance between bushing port edges 53! and 532. As desired, the supply ports 10, H and 12 and venting ports l4, l5 and 16 may be formed with their edges respectively arranged as shown or may be formed with all of the effective trailin edges 13-43 of the supply ports arranged in the same transverse plane and effective leading edges 11-11 arranged in different transverse planes. A further alternative is the arrangement of all leading edges 1111 in the same transverse plane and the trailing edges 13-13 in different transverse planes.

The outward end of the main bushing section l8 may be provided with a flange 80 circumambient of the plunger 42 preferably within the chamber 49 and this flange may be provided with three pairs of diametrically opposed longitudinally extending ways or slots 8l--Bl with each pair arranged about 120 from the successive pair similar to the arrangement of the pairs of ports in the plunger. A pair of opposed slots 8l-8| are adapted to receive the opposite ends of the pin 68 as shown in Figure 1 for positioning of a pair of supply and venting ports of the plunger in selected communicative relation to the port end of passage 53.

As described above, the high pressure gasket 28 may predetermine the position of the plug 30 in the high pressure end of the casing bore ll. Such predetermination of position may additionally be attained, as indicated, by causing the end of the plug 3!! to engage the high pressure end of the bushing l8 such as at 9| as shown in Figure 1 after the gasket 28 has been suitably deformed and depressed in the recess 25. The provision of the gasketing 28 makes possible the use of such structure without necessitating accurate lining up of cooperating surfaces of plug 30 and bushing section l8 at 9|.

It is intended that all matter contained in the above description or shown in the accompanying drawing shall be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described, and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.

Having described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. In a high pressure fluid pump the combination comprising, a casing having a bore and a relatively low pressure fluid passage communicating therewith, said bore being counterbored to provide two shoulders, one on each side of the fluid passage, a bushing in said bore fitted thereto inwardly of the pair of shoulders and having a fluid passage extending therethrough for communication with the casing fluid passage and two shoulders, one on each side of the bushing fluid passage and with each paired for cooperation with one of the bore shoulders and a high pressure end, a high pressure seal being provided at the cooperating pair of shoulders inward of the passages, and a low pressure sealing gasket of deformable material between the cooperating pair of shoulders outward of the passages, said pair of shoulders at the high pressure seal solely cooperating to limit movement of said bushing into the bore for proper location thereof.

2. In a high pressure fluid pump the combination comprising, a casing having a bore and a relatively low pressure fluid passage communicating therewith, said bore being counterbored to provide two shoulders, one on each side of the fluid passage, a bushing in said bore fitted thereto inwardly of the pair of shoulders and having a fluid passage extending therethrough for communication with the casing fluid passage and two shoulders, one on each side of the bushing fluid passage and with each paired for cooperation with one of the bore shoulders and a high pressure end, a high pressure seal being provided at the cooperating pair of shoulders inward of the passages, a low pressure sealing gasket of deformable material between the cooperating pair of shoulders outward of the passages, said pair of shoulders at the high pressure seal solely cooperating to limit movement of said bushing into the bore for proper location thereof, said bushing having its high pressure end recessed adjacent the bore wall to provide a gasket seat, a gasket of deformable material on said seat, and a plug forced into the bore with the last-mentioned gasket compressed between said bushing and said plug.

3. In a high pressure fluid pump the combination comprising, a casing having a bore and a relatively low pressure fluid passage communicating therewith, said bore being counterbored to provide two shoulders, one on each side of the fluid passage, 2. bushing in said bore fitted thereto inwardly of the shoulders and having a fluid passage extending therethrough for communication with the casing fluid passage and two shoulders, one on each side of the bushing fluid passage and with each paired for cooperation with one of the bore shoulders and a high pressure end, a high pressure gasket between the cooperating pair of shoulders inward of the passage having a certain area of seating therewith, and a low pressure sealing gasket of deformable material between the cooperating pair of shoulders outward of the passages having an initial area of seating therewith less than that of said high pressure gasket.

4. In a high pressure fluid pump the combination comprising, a casing having a bore and a relatively low pressure fluid passage communicating therewith, said bore being counterbored to'provide two shoulders, one on each side of the fluid passage, a bushing in said bore fitted thereto inwardly of the shoulders and having a fluid passage extending therethrough for communication with the casing fluid passage and two shoulders, one on each side of the bushing fluid passage and with each paired for cooperation amass? ing. arranged" at an oblique: angle to the axis of:

said bushing, and a lowv pressure sealing gasket of" deformable material between the last-mentioned pairof shoulders with the oblique angularly arranged shoulden'providing an initial area of gasket seating less than: that of said highpressure gasket and causing gasket deformation for effective low pressure, sealing.

; In a high pressure fluid pump the combination comprising, a casing having a: bore and a,

relatively low: pressurefluid'passage communicating. therewith, said" bore being" counterbored to provide two shoulders, one on each side of the fluid passage, a bushing in said bore fitted thereto inwardly of theishoulders and having a fluid passage extending therethrough for communication with th casing fluid passage and two shoulders, one on each side of the bushing fluid passage and with each paired for cooperation with one of the bore shoulders and a high pressure end, a high pressure gasket between the cooperating pair of shoulders inward of the passages and a low pressure sealing gasket of deformable material softer than that of the high pressure gasket between the cooperating pair of shoulders outward of the passages.

6. In a high pressure fluid pump the combination comprising, a casing having a bore and a relatively low pressure fluid passage communicating therewith, said bore being counterbored to provide two shoulders, one on each side of the fluid passage, a bushing in said bore fitted thereto inwardly of the shoulders and having a fluid passage extending therethrough for communication with the casing fluid passage and two shoulders, one on each side of the bushing fluid passage an with each paired for cooperation with one of the bore shoulders and a high pressure end, a high pressure gasket between the cooperating pair of shoulders inward of the passages having a substantial area of seating therewith, one of said outwardly paired shoulders being arranged at an oblique angle and the other thereof substantially at right angles to the axis of said bushing, and a low pressure sealing gasket ring of deformable material initially having substantially parallel outward and inward faces arranged substantially at right angles to the axis thereof confined between the last-mentioned pair of shoulders with the oblique angularly arranged shoulder initially having a relatively small area of gasket seating and causing gasket deformation for eifective low pressure sealing.

7. In a high pressure fluid pump the combination comprising, a casing having a bore and a relatively low pressure fluid passage communicating therewith, said bore being counterbored to provide two shoulders, one on eachside of the fluid passage, a bushing in said bore fitted thereto inwardly of the pair of shoulders and having a fluid passage extending therethrough for communication with the casing fluid passage and two shoulders, one on each side of the bushing fluid passage and with each paired for cooperation with one of the bore shoulders and a high pressure end, a high pressure seal being provided at the cooperating pair of shoulders inward of the passages, a low pressure sealing gasket of deformable material between the cooperating pair of shoulders outward of the passages, said pair of shoulders: at, the high; pressure; seal. solely coopcrating to limit movement of; said bushing into.

the bore forproper locatiolnthereof', said bushing. having its high pressure-end:provided with gasket seating surfaces, a plugforced: into the bore and having seating surfaces,- and a gasket of deformabl material compressed between said'bushing and: said' plug seating. surfaces, one of thebushing: and" plug seating surfaces being initially of: a certain area and of! increased area as said plug is forced, to final location determined: by such seating of increased area.

8... In a. high pressure fluid pump the combination comprising; a casing having a bore and a relatively: low pressure fluid passage communicating therewith, said bore being counterbored toprovide two shoulders; on on each side of the fluid passage, ar-bushing insaid bore fitted thereto inwardly. off the pair of! shoulders and having a fluid" passage extending therethro'ugh for communication with the casing fluid passage and two shoulders, one on each side of the bushing fluid passage and with each paired for cooperation with one of the bore shoulders and a high pressure end, a high pressure seal being provided at the cooperating pair of shoulders inward of the passages, a low pressure sealing gasket of deformable material between the cooperating pair of shoulders outward of the passages, said pair of shoulders at the high pressure seal solely cooperating to limit movement of said bushing into the bore for proper location thereof, said bushing having its high pressure end provided with gasket seating surfaces, a plug forced into the bore and having seating surfaces, and a gasket of deformable material compressed between said bushing and said plug seating surfaces, said seating surface on the bushing being of such configuration with respect to cooperating surface of said last-mentioned gasket as to provide a certain initia1 area of seating and when the plug is forced into the bore an increased area of seating whereby to determine final plug location.

9. In a high pressure fluid pump the combination comprising, a casing having a bore and a relatively low pressure fluid passage communicating therewith, said bore being counterbored to provide two shoulders, one on each side of the fluid passage, a bushing in said bore fitted thereto inwardly of the pair of shoulders and having a fluid passage extending therethrough for communication with the casing fluid passage and two shoulders, one on each side of the bushing fluid passage and with each paired for cooperation with one of the bore shoulders and a high pressure end, a high pressure seal being provided at the cooperating pair of shoulders inward of the passages, a low pressure sealing gasket of deformable material between the cooperating pair of shoulders outward of the passages, said pair of shoulders at the high pressure seal solely cooperating to limit movement of said bushing into the bore for proper location thereof, said bushing having its high pressure end provided with gasket seating surfaces, a plug forced into the bore and having seating surfaces, and a gasket of deformable material compressed between said bushing and said plug seating surfaces, said gasket engaging only a portion of the plug seating surfaces from inception of placement of the plug in the bore with a substantial portion of the remainder of plug seating surfaces engaging the high pressure end of said bushing to determine final plug location.

10. In a high pressure fluid pump the combination comprising, a casing having a bore tenninating in a high pressure end, a bushing in said bore fitted thereto adjacent the high pressure end, said bushing having its high pressure end recessed adjacent the bore wall to provide a gasket seat having at least a portion thereof arranged at an oblique angle to the axis of said bushing, a gasket ring of deformable material on said seat with an outside surface engaging the bore wall, and a plug forced into the bore with said gasket ring compressed between said bushing and said plug and with the oblique angularly arranged portion causing gasket deformation for effective fluid sealing and an increase in area of gasket seating to determine final plug location.

11. In a high pressure fluid pump the combination comprising, a casing having a bore termimating in a high pressure end, a bushing in said bore fitted thereto inwardly of the high pressure end thereof, said bushing being provided with a substantially flat shoulder arranged substantially normal to the axis thereof and an adjacent seating surface conforming substantially to that of a truncated cone, a gasket ring of deformable material having an outside surface engaging the bore wall and substantially parallel outward and inward faces arranged substantially at right angles to the axis thereof with one engaging against said shoulder, and a plug forced into the bore engaging the other face thereof with the gasket ring compressed between said plug and said bushing and the seating surface causing gasket deformation for effective fluid sealing, said gasket ring initially seating solely against said coned surface whereby said shoulder provides increased area of seating to determine final plug location.

WARNER T. TABB. 

